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An appropriate distortion analysis requires an accurate modeling of the MOSFET drain current derivatives. We discuss and develop a compact MOSFET modeling scheme in order to obtain accurate descriptions of the drain current and its derivatives up to the 5th order. We have analyzed the physical effects which govern the behavior of the 3rd derivative in long and deep-submicron channel MOSFETs. Our modeling agrees well with experimental data and describes continuous transitions between operating regimes, thanks to the use of continuous functions, which do not introduce any artificial peaks.

This paper analyzes signal separation and distortion in a feedforward blind source separation (BSS) applied to convolutive mixture environment. In the BSS learning, a separation block is adjusted so as to make the output signals statistically independent. One direction for this adjustment is to extract only one signal source at a single output. The other direction is to make the output signal spectra white. The second direction causes signal distortion and conflicts with the first direction. This confliction prevent signal separation. These relations are also dependent on a length of the impulse responses in the mixture and the filter length in the separation block. These properties are theoretically analyzed and are investigated through simulations using the white signal sources and the speech signal sources.

In this article we present the main features and structural relationships between thortveitite-type and thortveitite-like germanates compounds. We describe in detail the crystal structures, how they are built and the difference between them. Bond-valence and polyhedra distortion analysis are made and crystal structure stability ranges are given.

The procedure of plasticity‐based distortion analysis (PDA) directly mapping cumulative plastic strains into elastic models using equivalent thermal strains was developed and applied to the investigation of the characteristic relationship between cumulative plastic strains and angular distortion in fillet welded thin plate T‐joints. The PDA successfully demonstrated the validity of the unique relationship between cumulative plastic strains and distortion and the applicability of a linear elastic model in welding‐induced distortion analysis. The PDA procedure also provided the quantitative relationship between six cumulative plastic strain components and angular distortion of fillet welded T‐joints, showing the importance of shear component in angular distortion.

In recent research on shape-from-shading much focus has been put on the minimization approaches and on the Tsai and Shah linear approach. We presented a novel non-linear approach using the Jacobi iterative method, which is as simple in implementation as the linear method and as accurate as those minimization ones. This paper first, analyzes our method to clarify how the shape distortion is generated. Then, the effects of the bi-directional estimation of the shape on reducing the distortions are examined with numerical examples.

Distortion associated with memory-less nonlinear sensors is analyzed and several distortion compensation techniques are presented. Sensor nonlinearity is considered a defect in sensory systems because it introduces distortion into the system. Due to the fact that no efficient technique is available to deal with the issues related sensor nonlinearity, nonlinear primary sensors tend to be ignored. In this paper, we point out that there are certain advantages of using nonlinear sensor and nonlinear distortion caused by sensor nonlinearity may be completely compensated. A robust and efficient signal recovery procedure is derived to facilitate the design of nonlinear sensors. Not having an accurate sensor will result in errors and it is shown that the error can be minimized with a proper choice of a convergence parameter whereby stability of the developed algorithm is established. Simulation results are presented to validate the algorithms developed.Copyright © 2003 by ASME

Due to continuous advances in technology the MOS transistor has scaled down rapidly. Whereas 3μm CMOS was used in the middle of the eighties, technologies with effective gate lengths of 0.35μm are in use in 1997. In these small devices several physical effects play a much larger role than in transistors of older technologies. Some of these effects have given rise to additional technological steps in the processing of a MOS transistor, such as the use of lightly-doped drains. As a result, a modern deep submicron transistor is a more complicated structure than a transistor of older technologies.

A novel input buffer for very high speed and high resolution track-and-hold amplifiers has been developed in BiCMOS technology. The configuration retains the benefits of a cascode configuration in terms of distortion and adaptability to various advanced switched-emitter (source)-follower based architectures while maintaining supply requirements similar to a conventional degenerated common emitter amplifier. To demonstrate the advantages of the presented architecture a distortion analysis has been carried out. The closed form formulas show very good agreement with Spectre ® simulations using complete models.

Small-signal distortion analysis requires the second-order and third-order derivatives of the model equations. The use of numerical differentiation schemes enables a fast and model-independent derivation. We propose here two efficient algorithms. Both use a central differential quotient. One algorithm is based on a Romberg scheme and finds iteratively an optimal step size. The other algorithm was developed especially for bipolar elements. Here, a logarithmus naturalis transforms the equations to the ln-plane, where they behave nearly linear. This makes a step-size control for the differentiation superfluous. The methods have been realized in SPICE for complex modelled bipolar and MOS transistors.

The principle of the spectral-encoding technique, one of the single-shot techniques for measurement of arbitrary pulsed terahertz (THz) signals, or T-rays, is demonstrated theoretically and through simulation. For single-cycle input THz pulse (bipolar wave form), THz signal could be retrieved faithfully under certain conditions, while for the multicycle input case, the THz signal cannot be retrieved without any distortion. However, there is an optimal length of the chirped-probe-pulse, corresponding to the characteristic time of the multicycle THz field, to minimize the distortion in the retrieved THz signal. Three main possible sources of distortions from both bipolar and multicycle THz signals are analyzed systematically. The first distortion originates from the mismatch of the optimal duration Tco of the chirped-probe-pulse and the T-ray length T. The second one is relevant to the spectrum bandwidth of the probe pulse. The third one occurs when the modulation depth k⪡1 is not satisfied. It comes from t...

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Centrifugal distortion analyses of combined infrared-microwave data sets of H 2 17 O and H 2 18 O have been performed. These analyses make possible critical evaluation of data points and results in substantially improved energy levels. The Fraley-Rao interpolation rule for the prediction of H 2 17 O energy levels is examined and extended.

One hundred and eleven new rotational transitions of HNO 3 have been measured in the millimeter-microwave region. This data set is the basis for a centrifugal distortion analysis and for the calculation of a complete set of energy levels through J = 50. The constants which result from this analysis are (in megahertz): A = 13 011.0287 ± 0.0057, B = 12 099.8611 ± 0.0057, C = 6260.6391 ± 0.0006, Δ J = (14.038 ± 0.026) × 10 −3 , Δ JK = (−20.1780 ± 0.0037) × 10 −3 , Δ K = (7.4153 ± 0.0108) × 10 −3 , δ J = (1.1828 ± 0.00039) × 10 −3 , δ K = (−20.5648 ± 0.0046) × 10 −3 , H J = (−9.84 ± 3.82) × 10 −8 , H JK = (−9.933 ± 0.367) × 10 −8 , H KJ = (1.03 ± 0.12) × 10 −7 , h J = (−9.241 ± 0.127) × 10 −9 , h JK = (−1.398 ± 0.032) × 10 −7 , and h K = (1.135 ± 0.027) × 10 −6 .

The millimeterwave spectrum of fluoroacetonitrile (CH2FCN) in the ground state has been investigated in the region between 50 and 150 GHz. The transitions have been fitted to a Hamiltonian using three rotational constants, five quartic and seven sextic centrifugal distortion constants in the symmetric top reduction by van Eijck and Typke and in the s-reduction of Watson. Further Watson's "determinable constants" have been calculated.

The rotational absorption lines of the molecule dimethylallene in the vibrational ground state deviate from a rigid rotor pattern by shifts due to centrifugal distortion and by shifts and splittings due to methyl top internal rotation. By enlarging the number of previously measured lines it has been possible to apply successfully a Watson-type centrifugal distortion formula and to analyze the resulting “effective rigid rotor” rotational constants for the remaining contributions due to internal rotation and centrifugal distortion. Care has been taken to calculate or at least estimate the separate contributions and compare their magnitudes.

An analysis of the microwave spectrum of HNSO and DNSO has been performed, extended with respect to a preceding work, in order to determine the first-order P 1 centrifugal distortion constants. From the b-type spectrum of DNSO, not previously assigned, the rotational constant A of this species has been evaluated. The H–N bond r s distance has been calculated to be 1.0272±0.0001 A.

Measurements of R and Q branch a-type pure rotational transitions in the frequency range from 8 GHz to 220 GHz are reported for ketene-d1 and ketene-d2. The microwave and millimeter wave transitions were analysed in terms of Watson’s reduced Hamiltonian, including the sextic terms HKJ and HJK. The values of the inertial defect and the τ defect obtained from the centrifugal distortion analysis are in accord with the planar model for the ketene molecule.

Centrifugal distortion analyses based entirely on high-quality infrared data are carried out for the ground vibrational states of H 2 16 O, H 2 17 O, and H 2 18 O. As a result of the analyses, the values of 27 rotation and distortion constants for each species are determined. By using these constants it was possible to improve considerably the accuracy of the literature values for rotational energy levels at high J τ , especially for H 2 17 O and H 2 18 O. The experimental values for the energy levels are deduced from the observed rotational transitions constituting the fitted data.

PRINCIPLES of similitude modeling have been applied to develop design conditions and pre-diction equations to perform standard ROPS tests using small scale models. Design conditions related to the time scale and force scale were distorted. Compensated distortion analysis was applied to account for distortion in the force scale. Distortion in the time scale was accounted for by developing a prediction factor using a mathematical model. Two model ROPS systems of 1/4-scale and 1/8-scale were designed and built. It was found feasible to predict ROPS behavior in the static test as well as the standard sideways overturn test.

A detailed centrifugal distortion analysis of the rotational spectrum of cyclopropenylidene C 3 H 2 has been deduced from its millimeter wave spectrum. C 3 H 2 , a ring molecule recently discovered by Thaddeus and co-workers, has been efficiently produced by a very weak rf discharge in allene, C 3 H 4 . Fractional abundance as high as one percent has been obtained, which is explained by the long lifetime of the molecule, measured to be about 300 ms at 30 mTorr.

A treatment of centrifugal distortion analysis up to P 6 -terms which is advantageous in several respects is presented. The considerations of van Eijck in the treatment of the P 4 -terms have been extended to the higher order P 6 -terms. A reduced Hamiltonian is proposed which is convergent in the proper representation also for nearly symmetric top molecules. The results of a centrifugal distortion analysis based on this Hamiltonian are given for dimethylsulfoxide (DMSO) and carbonyl fluoride (COF 2 ). The results for COF 2 show a remarkable improvement in the correlations of the fitted parameters and in the numerical stability compared to Carpenter's analysis of the same experimental data.

Applying a bootstrap approach to transition assignment, a first-order centrifugal distortion analysis has been performed on 1,3-dioxane, tetrahydropyran, and piperidine (axial NH conformer). Q-branch transition frequencies for J up to 32 have been combined with previously published or remeasured frequencies for low J, R-, and Q-branch transitions to yield values for the quartic centrifugal distortion parameters. Comparison is made between the results obtained using two forms of the quartic Hamiltonian.

The microwave spectrum of ethyl iodide has been reinvestigated between 4 and 80 GHz. A total of 181 ground-state transitions with J ≤ 26 and F ≤ 57 2 have been analyzed using numerical diagonalization of the quadrupole Hamiltonian. The following rotational and quadrupole coupling constants have been determined (in MHz): A ′ = 29 116.321; B ′ = 2979.5639; C ′ = 2796.4520; χ aa = −1478.111; χ bb = 564.464; χ cc = 913.648, and χ ab = 896.38. The quadrupole coupling constants have been transformed to their principal axis system. All the quartic centrifugal distortion constants have been significantly determined, the standard deviation of the fit being only σ = 31 kHz.

In the rotational spectrum of acetone, 52 new quartets (up to 300 GHz, J≤30) have been measured. Because the barrier hindering internal rotation is low (s = 21), a new computer program based on the Internal Axis Method has been developed. It has allowed us to satisfactorily fit the spectrum and to accurately determine the rotational constants, centrifugal distortion constants, and the three internal rotation parameters.

The centrifugal distortion analysis of the pure rotational spectrum of pentafluorobenzene in the frequency region of 8 to 18 GHz involvingJ upto 54 has yielded the following rotational and quartic centrifugal distortion constants: $$\begin{gathered} A'' = 1480 \cdot 8665 \pm 0 \cdot 0026 MHz, \tau = - 1 \cdot 751 \pm 0 \cdot 20 kHz, \hfill \\ B'' = 1030 \cdot 0782 \pm 0 \cdot 0025 MHz, \tau _2 = - 0 \cdot 567 \pm 0 \cdot 066 kHz, \hfill \\ C'' = 607 \cdot 5152 \pm 0 \cdot 0026 MHz, \tau _{aaaa} = - 0 \cdot 765 \pm 0 \cdot 068 kHz, \hfill \\ \tau _{bbbb} = - 0 \cdot 612 \pm 0 \cdot 065 kHz, \hfill \\ \tau _{cccc} = - 0 \cdot 547 \pm 0 \cdot 068 kHz. \hfill \\ \end{gathered} $$

The framework distortion of C 3 CZCC 3 fragments is largely controlled by local strain release. It is not limited to the C 3 C- tilt previously mentioned in other compounds. We show a very significant opening of angle CZC and an important symmetrical distortion of C 3 C- groups by expansion (Z = NO, S, O) or compression (Z = C, NH, NMe, NS, P, Si). We discuss the effect upon the apparent size of tertiary groups.

In this paper we analyze the characteristics of a crosscorrelation method for measuring the impulse response of an unknown system. This analysis may also be of some interest in the area of synchronization of pseudonoise systems. In the first part of the paper a closed-form expression for the main component of the probing pulse is derived. This result may be used to quickly estimate the effect of various system parameters on the measurement's accuracy. In the second part results are presented for two system configurations.

The centrifugal distortion analysis of the microwave spectrum of the N-gauche lone-electron-pair trans (NGLT) rotameric form of allylamine has been carried out in the frequency region 5–40 GHz and up to J = 29 in its ground vibrational state. The analysis gives effective rotational constants and all the quartic centrifugal distortion constants.

The rotational spectrum of diazomethane, H2CNN, was investigated in the frequency range 100 to 400 GHz. Due to the C2v symmetry of the molecule, which is planar, only a-type dipole transitions were observed. The measurements were analyzed using Watson's S-reduced Hamiltonian. A detailed centrifugal distortion analysis yielded the following rotational and quartic centrifugal distortion constants: A = 272 979.1(8.1) MHz, B = 11 305.42697(45) MHz, C = 10 845.22028(47) MHz, DJ = 4.14620(74) kHz, DJK = 396.817(92) kHz, DK = 22.0 MHz (fixed), d1 = −192.55(42) kHz, d2 = −57.27(39) Hz. Some sextic and higher-order distortion constants were determined and are discussed.

The 1 H and 13 C spectra have been analyzed fully for 5-thio-α- d -xylopyranose and in part for the β anomer. Comparison with our analyses for both anomers of 5-thio- d -glucopyranose and 6-thio- d -fructopyranose and with analyses of the analogous oxygen sugars for all three systems provides a general perspective for the characterization of ring distortions brought about by the presence of the sulfur atom within the ring. Puckering of the thio sugar ring is demonstrated in the α anomers of both the xylose and the fructopyranose by a decrease in axial-equatorial couplings and an increase in equatorial—equatorial couplings. The β anomers of 5-thioglucose and 5-thioxylose appear to be more resistant to puckering, possibly because of the buttressing effects of numerous adjacent equatorial groups. These conformational factors may be responsible in part for the decreased stability of the β thio sugar, relative to the α anomer, in comparison with the oxygen analogues.

The assignment of rotational transitions of nitric acid was extended up to J = 74 between 18 and 40 GHz. The newly measured transition frequencies were combined with previously reported transition frequencies in order to adjust all three rotational constants, five quartic, and seven sextic distortion constants in a least-squares fit: B a = 13011.025(5) MHz, B b = 12099.855(5) MHz, B c = 6260.641(5) MHz, Δ j = 14.00(3) kHz, Δ JK = − 20.168(4) kHz, Δ K = 7.44(1) kHz, δ J = −1.1820(2) kHz, δ K = 20.566(5) kHz, Φ J = −0.16(4) Hz, Φ JK = −0.086(4) Hz, Φ KJ = 0.052(13) Hz, Φ K = 0.11(3) Hz, ϕ J = 0.00952(6) Hz, ϕ JK = 0.135(3) Hz ϕ K = −1.14(3) Hz (oblate III r representation). An improved harmonic force field of nitric acid was obtained from ab initio calculations which were appropriately scaled in order to reproduce the observed vibrational frequencies. The quartic centrifugal distortion constants calculated from this harmonic force field are in good agreement with those obtained from microwave observations.

The microwave rotational spectrum of difluoramine (NF 2 H) has been analyzed in the frequency region 15–36 GHz involving rotational levels up to J = 19. The analysis gives refined rotational constants and all quartic centrifugal distortion constants. These constants have been used to predict additional Q -branch transitions of the molecule in the frequency region 5–95 GHz.

The ν1−2ν2 Fermi diad of OF2 at 928 cm−1 was investigated by IR-MW double resonance using CO2 and N2O lasers. Using the data of Morino (ref. 1) and the additional rotational transitions measured in this work, a partial distortion analysis of the states (1,0,0)′ and (0,2,0)′ could be carried out. The accurately determined frequencies of five IR transitions in the ν′1 band and of two in the ν′2 band allowed the band centres to be calculated in both cases.

A three-dimensional distortion analysis was made of seven indexing-investment systems and six indexing-remount systems. Measurements were made to within ±0.005 mm with a Nikon Profile Projector and a linear variable differential transformer (LVDT); distortions (linear and rotational) were calculated by means of a PDP 11/40 computer system. Mean vector displacements, Δ X 2 + Δ Y 2 + Δ Z 2 , were calculated, and a statistical evaluation of the data was completed. The results of the study indicate: 1.The zinc oxide-eugenol (ZOE) indexing-investment system produced a narrower range and a significantly smaller mean distortion than the other six indexing-investment systems. 2.The ZOE-stone remount technique showed significantly less distortion than the ZOE-low-fusing metal or the ZOE-acrylic resin techniques. 3.The polyether-stone remount technique demonstrated significantly less distortion than either the polyether-low-fusing metal or the polyether-acrylic resin system. 4.The polyether-stone remount system was not significantly different from the ZOE-low-fusing metal system. 5.The ZOE-stone remount technique demonstrated a smaller range of distortions, but those distortions were not significantly different from those of the polyether-stone remount technique.

Centrifugal distortion effects in the microwave rotational spectrum of Formaldoxime (CH 2 NOH) have been investigated. The centrifugal distortion analysis makes possible the accurate calculation of rotational and centrifugal distortion constants. Distortion corrected rotational constants have also been obtained.

The rotational spectrum of HDS in the ground vibrational state has been studied by microwave techniques. Twenty-seven new transitions have been measured in the millimeter and submillimeter wavelength region. These have been combined with other microwave measurements of HDS for a centrifugal distortion analysis based entirely on microwave data; it has been necessary to include both P 4 and P 6 distortion effects in the analysis. The results for the effective rotational constants and quartic distortion constants are (in Mc/sec): a = 292 351.303 ± 0.135, B = 147 861.801 ± 0.054, C = 96 704.119 ± 0.054, Δ J = 2.6134 ± 0.0015, Δ JK = 28.6933 ± 0.0097, Δ K = −11.297 ± 0.019, δ J = 0.8554 ± 0.0008, and δ K = 19.4078 ± 0.0085. Energy levels through J = 7 have been computed for HDS.

The rotational spectrum of HDO in the ground vibrational state has been studied in the millimeter and submillimeter microwave region. Twenty‐one previously unreported transitions have been measured and assigned. These data have been combined with previous measurements on HDO for a centrifugal distortion analysis based entirely on microwave measurements. In the analysis distortion effects through P10 are included, although only a partial set of terms in P8 and P10 is found to be necessary. The results for the rotational constants, quartic and sextic distortion constants are (in megacycles per second): A=701 931.50 ± 0.22, B=272 912.60 ± 0.11, C=192 055.25 ± 0.10, ΔJ= 10.8375 ± 0.0058, ΔJK=34.208 ± 0.036, ΔK=377.078 ± 0.026, δJ=3.6471 ± 0.0014, δK=63.087 ± 0.035, HJ=1.128 × 10−3 ± 0.099 × 10−3, HJK=7.344 × 10−2 ± 0.092 × 10−2, HJK=−2.740 × 10−1 ± 0.022 × 10−1, HK=1.4651 × 100 ± 0.0027 × 100, hJ=6.546 × 10−4 ± 0.150 × 10−4, hJK=3.096 × 10−2 ± 0.037 × 10−2, and hK=5.549 × 10−1± 0.053 × 10−1.